Preparation of ethylenebisiminodiacetic acid and salts thereof



Patented Apr. 15, 1947 PREPARATION OF ETHYLENEBISIBIINO- -DIACETIC ACIDAND SALTS THEREOF Edryd Gwylfa Parry, Blackley,

Manchester,

England, assignor to Imperial Chemical Industries Limited, a corporationof Great Britain No Drawing. Application July 21, 1944, Serial No.

546,059.v In Great Britain July 28, 1943 7 Claims. (Cl. 260534) :Thisinvention relates to a process for the manufacture ofethylenebisiminodiacetic acid and salts thereof. 7 7

-It has been proposed to manufacture ethylenebisiminodiacetic acid by aprocess whereby ethylenediamine is condensed with the sodium salt ofmonochloracetic acid in presence of sodium carbonate.

g It has also been proposed to manufacture polyamino carboxylic acidnitriles or the corresponding acids or derivatives thereof, by a processwhich comprises causing hydrocyanic acid and aldehydes or ketones to acton primary or secondary polyamines, preferably in the presence ofcatalysts, while using hydrocyanic acid and aldehydes or ketones in suchmolecular proportions that at least 2 nitrile radicles are introduced insaturated fatty acids for example oleic acid. The

the molecule and if desired saponifying the nitriles obtained. Forexample ethylene diamine is condensed with formaldehyde and hydrogency-. anide in presence of calcium cyanide to giveethylenebisiminodiacetonitrile which may be hydrolysed to giveethylenebisiminodiacetic acid.

We have now found that ethylenebisiminodiacetic acid can be madedirectlyfrom ethylene dihalides by interacting them with salts of iminodiaceticacid.

According to the invention, therefore. we provide a process for themanufacture of ethylenebisiminodiacetic acid which-comprises reacting anethylene dihalide with a water-soluble salt of irrii'nodiacetic acid. Iv I Ethylene dihalides which may be used according to the inventioninclude ethylene dichloride and ethylene dibromide.

- Water-soluble salts of iminodiacetic acid which it is preferred to useare the alkali metal or ammonium salts. 'Iminodiacetic" acid may be madeaccording to the method described by Eschweiler (Annalen, 1894, 278,230) whereby the corresponding dinitrile is produced by the interactionof hydrogen cyanide and hexamethylenetetramine and is then hydrolysedwith baryta.

Interaction of the ethylene dihalide and the iminodiacetic acid salt maybe carried out in presence of an acid-binding agent, but such an agentis. not essential. The interaction is desirably brought about inpresence of a solvent and for this purpose water, dioxan or a mixture ofdioxan and water are suitable. If desired emulsifying agents may be usedto facilitate dispersion of the ethylene dihalide in cases where thesolvent is such as not to dissolve this halide. Suitable emulsifyingagents include the sulphated long chain fatty alcohols and sulphonatedunreaction is but slow at atmospheric temperature and advisedly it isconducted at a higher temperature for example at -100" 0. under refluxThe reaction may, if desired, be carried out at pressures greater thanthe atmospheric.

Ethylenedisiminodiacetic acid may be isolated from the reaction productby acidification or, by evaporation of the reaction product there may beobtained the salt thereof. The material so obtained may be used forexample for dissolving lime soaps.

The invention is illustrated but not limited by the following examplesin which the parts are by weight:

I Example 1 10.6 parts of iminodiacetic acid, 50 parts of water and 8.6parts of sodium carbonate are stirred together until a solution isobtained. To this solution 4.4 parts of ethylene dichloride are addedand the mixture is stirred and heated under reflux at -90 C. during 20hours. It is then cooled to atmospheric temperature, 11.6 parts ofconcentrated hydrochloric acid areadded and the mixture'is then furthercooled to 0 C.

Ethylenebisiminodiacetic acid crystallises out and is filtered off,washed and dried.

Example 2 10.6 parts of iminodiacetic acid, 200 parts of water, parts ofdioxan and 12.7 parts of sodium carbonate are stirred together until asolution is obtained. To this solution 4 parts of ethylene dichloride(which corresponds to 0.5 mole of ethylene dichloride per mol ofiminodiacetic acid) are added and the mixture is stirred under reflux at85-90 C. during 20 hours. The solution is then concentrated byevaporation to about a seventh of its volume, 10 parts of concentratedhydrochloric acid are added and the mixture is cooled to 0 C. Ethylenebisiminodiacetic acid crystallises out and is filtered off, Washed anddried.

Example 3 I iminodiacetic acid crystallises out and is filtered off,washed and dried.

Example 4 19.8 parts of ethylene dichloride are added to 5 a SOIHtiOIliofi 26.6 'parts; of iminodi'acetic' acid (which corresponds to one mol'of ethylene dichloride per mol of iminodiacetic acid) in 150 parts ofwater containing also 31.8 parts of sodium carbonate. The mixtureisstirred under--reflux and heated in an oil-bath.=-of temperature 115C.-125 C. until the temperature of the mixture reaches 100 C. It is thenevaporated todry ness on a boiling water bath-and theresi'due is groundto a fine powder which c'ontains,'besides inorganic salts, the sodiumsalt" of'ethylenebise. iminodiacetic acid.

Example 5 Example 6 30 18.8 parts of ethylene dibromide areadded toazsolutiona of 13.3 parts: of. iminodiacetic .acid in 75 parts. i of.water: containing. also 15.9t-parts rof sodium carbonate. The mixture isstirred'gunderi r reflux and heated in an :oilbath at 115 C.-125 C..during 42 hours.v Ethylenebisiminodiacetic acid is. then. isolated. fromthe reaction .mixture as. described in Example .5.

Example? 12.4"parts of ethylenedichloride. areaddedlto a solution. of26.6 parts of. iminodiaceti'c .acid in 150."parts of water containing,also 21.21partsof sodium carbonate and. 0.2;par-t .offsulphonated' oleicacid. Thismixture. is stirred under. reflux 45 and heated in anoil-bathat 11579-125"; CLuntil the temperature of the mixture reaches 100 CI Themixture is then cooled to atmospheric temperature, 35.4 parts ofconcentrated,hydrochloric acid :are added and the mixture. is furthercooled.- to .0 0., when..ethylenebisiminodiacetic.acid.crystallisesout,is filteredoff, washedandidried.

I claim:

1. Procession the..-manufactur.e.-of ethylene bisiminodiaceticacid.which. comprisesheating. .at. a temperature of. about 75 to-100 C.an-.ethy1ene. dihalidev with a water-soluble. salt ofiiminodiraceticacid.

2. Process according to claim.- 1- wherein. the ethy-Ienedihalide isethylene-dichloride ands-thev salt ofiminodiacetic acidis thesodiumsalt.-.

3. In a process for the preparatiomofasaltsofethylenebisiminodiaceticacid the step which comprises reacting an ethylene dihalide withiminodiacetic acid inthe presence-ofantacid-binding. agent inaqueous"solution,:whereby;a prodnet containing a salt ofethylenebisiminodiacetic acid is obtained.

4. In a process for the preparation of salts of ethylenebisiminodiaceticacid the step which comprises reacting an ethylene dihalide withiminodiacetic' acid at aztemperature' .cfiabout C."'to"100"C;"in anaqueous 'medium' in the presence of a metal carbonate of the classconsisting of sodium carbonate, potassium carbonate andcalcium-carbonate, whereby a mixture containingthe:.ethylenebisiminodiacetio acid salt of the said metal is produced.

5: In a procession-preparing a mixture containing .the 'sodium'salt ofethylenebisiminodiacetic acid'the step which comprises heatingethyleneadichloride with iminodiacetic acid at a temperature of-Zabout80 C. to C. in an aqueousmedium in the presence of sodium carbonate,'and evaporating the resulting mixture to dryness whereby a residuecontaining inor- V ganic-salts and the sodium'salt ofethylenebisiminodiaceticacid is obtained;

6. In a process for preparing a mixture containing the sodium salt ofethylenebisiminodiacetic" acid thestep which comprises heating about19.8 parts by weight of ethylenedichloridewith" a'solution of about'26;6 parts' of iminodiacetic acid in parts of Water containing alsoabout 3'1.8-p'artsof sodium carbonate at a temperaturaof about 100 C.,and evaporating'the. resulting "mixture" to drynesswhereby a residue"containing inorganic I salts and the sodium saltofethylenebisiminodiacetic acid is obtained:

7 In' aprocess for'preparing compounds of the class-consisting ofethylenebisiminodia-cetic' acid. and" water-soluble salts thereof,thestep which comprises-heating an ethylene jdihalide at .a tem:-

perature "of about 80 to 100" C. with iminodiacetic acid in anaqueousmedium in the presence of a metal carbonate of the-class"consisting of sodiurn-carbonate, potassium carbonate, andicaicium-carbonate; I

EDRYDGWYEFA PARRY;

REFERENCESTCITED' The following references are of record 'inthefilerzof= thiswpatent:

UNITED. STATES: PATENTS 1 Number Name Date Re. 22,352 Teeters July' 20,1943 2,168,181 Ulrich et al Aug.11, 1939. 2,261,002" Ritter Oct; 28,1941 2,206,249 Daimler et a1; Ju1y2, 1940 2,097,864 Pl'a'tz' et alNov.2, 1937 FOREIGN; PATENTS.

Number, Country Date 446,737 British April21, .1936.

OTHER REFERENCES Hofmanmr, Beilstein (Handbuch. der Org. Chema). v.(itlr'ed; vol:-4,:192-2) .1oage251";v

Duvillienw Beilsteini (Handbuchz; ders: Org;

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